Winter is a wondrous time, filled with winter pleasures! However, for our furry, feathered, scaly, or otherwise friends, it can be fatal!
Luckily, the natural world plays host to many wonders, not least animals that hibernate! These clever critters sure have adapted their own amazing way to survive harsh conditions!
But, who are these animals, and how do they do it? Here are all the facts you need to know about hibernation, plus all the coolest animals that do!
What is Hibernation?
Hibernation is a behavior that certain animals engage in to survive harsh conditions. These animals go and hibernate in their dens or a safe spot to conserve energy.
The reason they do this is usually that the outside temperatures may be too cold to handle. Or, they do this during harsh months where their critical food and water supply may be limited.
You see, animals don’t have fridges or deep-freezers to store away extra food for indefinite periods of time! So, they’ve adapted to their habitat in their unique way by hibernating!
Instead of toughing it out in horrible conditions, they pile on the pounds during the plentiful months. Then, they slip away to hibernate away the harshest months!
Hibernation vs. Torpor
So, what is hibernation, then? Well, you may think of it as sleeping – however, it’s quite different! You see, it’s called torpor – which uses up even less energy.
Torpor is a survival mechanism that some animals can use to reduce their food and water intake. When in torpor, animals use minimal metabolic functions, essentially “switching off.”
However, there are two types of torpor – hibernation and daily torpor. If an animal goes into torpor for less than 24 hrs a day, it’s classed as a daily torpor, not hibernation.
But, if an animal goes into torpor for longer than 24 hrs at a time, it’s classed as hibernation! Hibernators include any animals that hibernate for these long periods of time.
Light Sleep Hibernators vs. True Hibernators
Though quite a few animals hibernate, not all are classed as “true hibernators.” What is a “true hibernator,” you may ask?
Well, just like torpor, hibernators fall into two main categories, too! These are light sleep hibernators and true hibernators.
Light sleep hibernators fall into torpor for more than a day, but they are easily woken or may wake frequently. During waking hours, they may eat or even venture outside for a short trip.
On the flip side, true hibernators are almost impossible to wake up during hibernation. As such, they use way less energy and usually don’t need to eat, drink, or move around!
What happens to animals that hibernate?
Hibernation usually lasts anywhere from a few days up to a few months! During this time, true hibernator animals’ heart rates, metabolism, and breathing rates drop drastically.
When animals and humans sleep or hibernate, we use fewer calories. So, hibernation is an excellent way for these animals to survive the harsh conditions they’ve adapted to survive in!
Hibernating animals don’t need to eat, move – or, in some cases, even go to the toilet, either! During this time, those few extra pounds gained during summer get used sparingly.
Light sleep hibernators will wake up a few times to snack on a stash of food or perform these functions, though. In fact, they may even venture out on milder days between periods of torpor.
Do cold-blooded animals hibernate?
So, you may be wondering if cold-blooded animals are also animals that hibernate? Well, the answer to that question is – yes, cold-blooded animals do also hibernate!
However, it’s usually called brumation when cold-blooded animals hibernate – so don’t get confused when you hear this new word!
However, as we know, cold-blooded creatures operate a little differently from your average mammals, though. So, brumation is slightly different from hibernation, too.
You see, during brumation, a reptile doesn’t truly sleep, may do so during hot months, and still need water. As such, they may wake up every few days to drink before going back to brumation!
Do animals hibernate during the summer, too?
Typically, hibernation is a way animals cope with cold conditions. However, you may be wondering if animals hibernate during hot conditions, too?
Well, the answer is yes! However, when animals exhibit similar hibernation behaviors in hot conditions, it’s called aestivation! So, what’s the difference?
Essentially, aestivation is very similar to hibernation, but it just happens during the hot months. Some animals aestivate because hot conditions can be just as harsh as cold! Why?
Well, if the weather is hot or dry enough, there may be no water or food to eat, just like during winters! As such, some animals have adapted to aestivate during these times.
19 Cool Animals that Hibernate!
So, now we’ve gone through the facts about hibernation, let’s find out which are the coolest animals that hibernate! These smart creatures sure know how to spend the winters!
1. The Bear
The bear is one of the most commonly known hi-bear-nators! They gorge on food in the summer months before heading to their dens to hibernate until Spring!
Wouldn’t you love to spend your winter this way?
- Bears hibernate for 5-7 months on average.
- Not all bears hibernate – it depends on the climate in which they’re living.
- Bears can hibernate for up to 100 days in a row.
- Bears are light sleep hibernators, waking easily during hibernation.
2. The Bat
Bats are another of the animals that hibernate! These small flying creatures keep themselves safe and snug during the winter months by hanging out in safe caves or caverns together!
- Bats usually hibernate for up to 6 months at a time.
- Usually, only bats in cold climates hibernate.
- Waking bats during hibernation can be fatal for them as they use up vital, unreplenishable fat stores when awake.
- Bats are true hibernators, hibernating for the full hibernation time without waking once.
3. The Bumblebee
Hibernation isn’t only for mammals, birds, and reptiles – insects such as bumblebees partake, too! However, only the new queen bumblebee hibernates to ensure the colony’s survival!
- Bumblebee queens can hibernate for up to 9 months at a time.
- Only new queen bees hibernate while the rest of the colony dies.
- When done hibernating, the queen bee will forage for food, start a new nest, and lay eggs.
- Bumblebees are true hibernators.
4. The Box Turtle
The box turtle is an ectotherm or cold-blooded reptile that brumates. However, he doesn’t necessarily need to find a den to brumate in; he simply retreats into his shell in a safe spot!
- Box turtles usually brumate anywhere from 4-20 weeks, depending on their location.
- Box turtles stop breathing completely while they brumate.
- Box turtles get their oxygen from water absorbed through the skin and blood vessels or by drinking during brumation.
- Box turtles aren’t true hibernators; they are brumators!
5. The Land Snail
The land snail does not only go into aestivation and hibernation – he can also withstand partial freezing! Yes, if parts of his body freeze during cold months, he simply thaws when it gets warm!
- Land snails can stay dormant in aestivation or hibernation for up to 3 years!
- Land snails can hibernate but can also go into aestivation to survive the arid months.
- Land snails seal up their shells with mucus to ensure they don’t dry out during aestivation.
- Land snails are true hibernators.
6. The Skunk
Pew! I’m sure you know these stinky fellows! Well, guess what? They’re also another of the animals that hibernate, albeit lightly!
- Skunks hide away in their dens close to water and food during hibernation.
- As skunks don’t go into full hibernation, they still get cold and need to huddle together to keep warm.
- Skunks enter into a state of torpor, periodically waking to eat.
- Skunks are light sleep hibernators.
7. The Wood Frog
Wood frogs are another hibernator that is frost-resistant! During hibernation, wood frogs stop breathing completely and can even form ice crystals in their blood without being hurt!
- Wood frogs can hibernate and be frozen for up to 8 months at a time.
- Wood frogs hibernate by bedding down in any available leaves or logs or in loose ground.
- Wood frogs are not so good at digging, hence why they choose to bed down anywhere easy to access.
- A high concentration of glucose in a wood frog’s vital organs prevents them from freezing and being damaged.
8. The Snake
Being typical cold-blooded creatures, snakes are another reptile that brumates! These slinky animals crawl away into dens, caverns, or burrows to sleep through the harsher months.
- Snakes can brumate for up to 8 months at a time.
- Snakes often brumate alongside hundreds of other snakes in burrows under the ground!
- When snakes brumate, they become lethargic and move very little.
- Snakes aren’t true hibernators – they brumate.
9. The Hedgehog
This cute but prickly creature is not uncommon in some urban areas. However, you may not see him for a while when he disappears to hibernate away the cold months!
- Hedgehogs usually hibernate for 5-7 months at a time.
- Hedgehogs may forego hibernation in the winter if the weather is mild enough.
- If temperatures get too cold, hedgehogs can wake temporarily to raise their body temperature.
- Hedgehogs are one of the few animals that are true hibernators.
10. The Chipmunk
Chipmunks – these cute and furry critters don’t deal with the cold so well! As such, they hide away in their dens, going into periods of torpor to pass the time!
- Chipmunks hibernate for up to 7 months during the winter.
- During hibernation, chipmunks wake up every few days to snack, move around, or even venture out on warmer winter days!
- Chipmunks go into a torpor for a few days or a week at a time, waking in between.
- Chipmunks are light sleep hibernators.
11. The Fat-Tailed Dwarf Lemur
Though not a likely suspect, the fat-tailed dwarf lemur is another hibernator. However, he’s more of an aestivator as he does this to avoid the harsh Madagascan droughts where he’s from!
- Fat-tailed dwarf lemurs can aestivate for up to seven months at a time.
- Fat-tailed dwarf lemurs are the only tropical primate known to hibernate!
- Fat-tailed dwarf lemurs are light sleep hibernators.
12. The Common Poorwill
Though you likely haven’t seen one around, common poorwills are, well, surprisingly common! But, what’s not so common about them, is that they are the only bird that hibernates!
- The common poorwill will hibernate when food is scarce.
- Common poorwills are nocturnal birds belonging to the nightjar family.
- The common poorwill can go into a state of torpor for extended periods of up to 3 months at a time, but typically less.
- The common poorwill is the only bird known to hibernate.
- Common Poorwills are light sleep hibernators.
13. The Deer Mouse
The deer mouse may be cute, but he’s known to sometimes carry a dangerous disease – Hantavirus. Lucky then that he hides away and hibernates during the winter!
- The deer mouse hibernates for the winter, storing food nearby beforehand during the plentiful autumn months.
- Deer mice often take up residence in homes during hibernation.
- Deer mice are natural carriers for the dangerous Hantavirus!
- Deer mice are true hibernators.
14. The Prairie Dog
The prairie dog is not actually a dog – he’s a rodent. As such, though he may be a big rodent, he still needs to slow down during the winter months!
- Prairie dogs hibernate for up to 6 months during the winter.
- Prairie dogs cuddle up together in their burrows to keep warm during winter!
- Depending on how mild conditions are, some prairie dogs may not hibernate at all.
- During very cold months, prairie dogs will hide out in their burrows with plenty of stores of food!
- Prairie dogs are light sleep hibernators.
15. The Ground Squirrel
The ground squirrel does much as the prairie dog does – he hides out the winter months! However, he’s a true hibernator who can go into torpor for the entire time!
- The ground squirrel will hibernate for around 4-9 months during winter.
- Ground squirrels are animals that hibernate but may venture out on warmer winter days!
- Ground squirrels are true hibernators.
16. Moths & Butterflies
Most moths and butterflies only live a short time and may or may not spend winter months as pupae or caterpillars. However, most adults that do live during winter need to go into diapause!
- Some moths, such as Winter or December moths, don’t hibernate – they can survive winters just fine.
- Moths and butterflies warm themselves through external heat sources.
- Some adult moths and butterflies produce chemicals that act as antifreeze to prevent the formation of ice crystals in their body.
- Some moths and butterflies migrate to warmer climates or hide out in houses to avoid cold conditions.
- Insects like moths and butterflies go into diapause; they don’t technically hibernate.
17. The Ladybug
The ladybug – this cute, little lady isn’t one for the cold and snow! No, she needs to hunker down for the winter. And, since she lives up to three years, she’ll need to do so a few times in her life!
- Most ladybugs take shelter under leaves, in tree stumps, or in empty cicada shells during winter!
- Ladybugs gather together to hibernate during autumn and won’t come out till around April.
- Ladybugs look for damp conditions, too, to ensure they stay hydrated during the winter.
- Ladybugs are insects, so their form of hibernation is actually called diapause.
18. The Raccoon
Raccoons are pretty resourceful creatures, so it’s no surprise they know how best to spend winter! Yes, they nap away the days warmly holed up together in their burrows!
- Raccoons may sleep for up to a month without waking during their hibernation.
- As raccoons are one of the animals that hibernate lightly, they wake to eat, move around, and even venture outside.
- Raccoons store up food in their burrows to eat during the winter months.
- Raccoons are light sleep hibernators.
19. The Marmot
Last but not least, the marmot is one of the most horrendous hibernators, spending over half his life in the act! Yes, hibernation is the only activity on this big rodent’s winter bucket list!
- Marmots hibernate for up to 8 months.
- During hibernation, a marmot’s heartbeat drops to 5-10 bpm, and he takes around two breaths per minute!
- The average marmot loses up to a fourth of his body weight during hibernation!
- Marmots are one of the longest hibernating true hibernators, going into torpor for months.
- Marmots are true hibernators.
Animals that hibernate may be rare, but they are well worth reading up on. After all, these unique creatures have adapted to survive the harshest conditions!
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